Shallow drilling of sediments on the eastern margin of the Eucla Basin (in 25 vertical rotary mud holes with a total penetration of ~1280 m) to test for secondary uranium mineralisation, although limited by drilling difficulties, has resulted in the discovery of anomalous radioactive zones associated with extensive lignite beds north and west of Pidinga Lake. Earlier, reconnaissance aerial radiometric surveys had identified the two main lakes in the area as containing the most near-surface radioactivity, although the measured radioactive highs are very localised and not related to the deepest portions of the lakes. A survey of the elevated area of sand dunes in the north-west found a number of unmapped outcrops of Precambrian basement, which on testing failed to show any obvious primary radioactive source. Significant occurrences of Tertiary lignite have been intersected in 57 of 97 uranium exploration drillholes drilled to date on SMLs 316, 365 and 367. Lignite also occurs just below the bottom surface of several of the local salt lakes. The beds occupy variable depths above an undulating Precambrian basement, but their reported thicknesses are extremely approximate due to the drilling and sampling methods used, since no coring has yet taken place which would give accurate results. Recommendations are therefore given for an exploratory work program within the SMLs to help delineate possible areas of greatest economic potential.